Class: ActiveCypher::Bolt::Transaction

Inherits:
Object
  • Object
show all
Includes:
Instrumentation
Defined in:
lib/active_cypher/bolt/transaction.rb

Overview

Manages transaction state (BEGIN/COMMIT/ROLLBACK) and runs queries within a transaction.

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Instrumentation

#instrument, #instrument_connection, #instrument_query, #instrument_transaction, #sanitize_config, #sanitize_params, #sensitive_key?

Constructor Details

#initialize(session, initial_bookmarks, metadata = {}) ⇒ Transaction

Initializes a new Transaction instance.

Parameters:

  • session (Session) —

    The session that owns this transaction.

  • initial_bookmarks (Array<String>) —

    Initial bookmarks for causal consistency.

  • metadata (Hash) (defaults to: {}) —

    Metadata from the BEGIN success response.



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# File 'lib/active_cypher/bolt/transaction.rb', line 16

def initialize(session, initial_bookmarks, metadata = {})
  @session = session
  @connection = session.connection
  @bookmarks = initial_bookmarks || []
  @metadata = metadata
  @state = :active
end

Instance Attribute Details

#bookmarks ⇒ Object (readonly)

Returns the value of attribute bookmarks.



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# File 'lib/active_cypher/bolt/transaction.rb', line 9

def bookmarks
  @bookmarks
end

#connection ⇒ Object (readonly)

Returns the value of attribute connection.



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# File 'lib/active_cypher/bolt/transaction.rb', line 9

def connection
  @connection
end

#metadata ⇒ Object (readonly)

Returns the value of attribute metadata.



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# File 'lib/active_cypher/bolt/transaction.rb', line 9

def metadata
  @metadata
end

Instance Method Details

#active? ⇒ Boolean

Checks if the transaction is active.

Returns:

  • (Boolean) 


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# File 'lib/active_cypher/bolt/transaction.rb', line 189

def active?
  @state == :active
end

#commit ⇒ Array<String>

Commits the transaction.

Returns:

  • (Array<String>) —

    Any new bookmarks.



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# File 'lib/active_cypher/bolt/transaction.rb', line 106

def commit
  raise ConnectionError, "Cannot commit a #{@state} transaction" unless @state == :active

  instrument_transaction(:commit, object_id) do
    # Send COMMIT message
    commit_msg = Messaging::Commit.new
    connection.write_message(commit_msg)

    # Read response to COMMIT
    response = connection.read_message

    case response
    when Messaging::Success
      # COMMIT succeeded

      @state = :committed

      # Extract bookmarks if any
      new_bookmarks = []
      if response.metadata.key?('bookmark')
        new_bookmarks = [response.metadata['bookmark']]
        @bookmarks = new_bookmarks
      end

      # Mark transaction as completed in the session
      @session.complete_transaction(self, new_bookmarks)

      new_bookmarks
    when Messaging::Failure
      # COMMIT failed
      @state = :failed
      code = response.metadata['code']
      message = response.metadata['message']

      # Mark transaction as completed in the session
      @session.complete_transaction(self)

      raise QueryError, "Failed to commit transaction: #{code} - #{message}"
    else
      raise ProtocolError, "Unexpected response to COMMIT: #{response.class}"
    end
  end
rescue ConnectionError
  @state = :failed
  # Mark transaction as completed in the session
  @session.complete_transaction(self)
  raise
end

#committed? ⇒ Boolean

Checks if the transaction is committed.

Returns:

  • (Boolean) 


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# File 'lib/active_cypher/bolt/transaction.rb', line 194

def committed?
  @state == :committed
end

#failed? ⇒ Boolean

Checks if the transaction is in a failed state.

Returns:

  • (Boolean) 


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# File 'lib/active_cypher/bolt/transaction.rb', line 204

def failed?
  @state == :failed
end

#rollback ⇒ Object

Rolls back the transaction.



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# File 'lib/active_cypher/bolt/transaction.rb', line 156

def rollback
  # If already committed or rolled back, do nothing
  return if @state == :committed || @state == :rolled_back

  instrument_transaction(:rollback, object_id) do
    # Send ROLLBACK message
    rollback_msg = Messaging::Rollback.new
    connection.write_message(rollback_msg)

    # Read response to ROLLBACK
    response = connection.read_message

    case response
    when Messaging::Success
      # ROLLBACK succeeded

    when Messaging::Failure
      # ROLLBACK failed - unusual but possible if connection is in a bad state
      response.metadata['code']
      response.metadata['message']

      # We don't raise here to ensure the rollback doesn't throw exceptions
    end
  rescue StandardError
    # We catch all exceptions during rollback to ensure it doesn't throw
  ensure
    # Always mark as rolled back and complete the transaction
    @state = :rolled_back
    @session.complete_transaction(self)
  end
end

#rolled_back? ⇒ Boolean

Checks if the transaction is rolled back.

Returns:

  • (Boolean) 


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# File 'lib/active_cypher/bolt/transaction.rb', line 199

def rolled_back?
  @state == :rolled_back
end

#run(query, parameters = {}) ⇒ Result

Runs a Cypher query within this transaction.

Parameters:

  • query (String) —

    The Cypher query to execute.

  • parameters (Hash) (defaults to: {}) —

    Parameters for the query.

Returns:

  • (Result) —

    The result of the query execution.



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# File 'lib/active_cypher/bolt/transaction.rb', line 29

def run(query, parameters = {})
  raise ConnectionError, "Cannot run query on a #{@state} transaction" unless @state == :active

  # Ensure query is a string
  query_str = query.is_a?(String) ? query : query.to_s

  instrument_query(query_str, parameters, context: 'Transaction#run', metadata: { transaction_id: object_id }) do
    # Send RUN message
    run_metadata = {}
    run_msg = Messaging::Run.new(query_str, parameters, run_metadata)
    connection.write_message(run_msg)

    # Read response to RUN
    response = connection.read_message
    qid = -1
    fields = []

    case response
    when Messaging::Success
      # RUN succeeded, extract metadata

      qid = response.metadata['qid'] if response.metadata.key?('qid')
      fields = response.metadata['fields'] if response.metadata.key?('fields')

      # Send PULL to get all records (-1 = all)
      pull_metadata = { 'n' => -1 }
      pull_metadata['qid'] = qid if qid != -1
      pull_msg = Messaging::Pull.new(pull_metadata)
      connection.write_message(pull_msg)

      # Process PULL response(s)
      records = []
      summary_metadata = {}

      # Read messages until we get a SUCCESS (or FAILURE)
      loop do
        msg = connection.read_message
        case msg
        when Messaging::Record
          # Store record with raw values - processing will happen in the adapter
          records << msg.values
        when Messaging::Success
          # Final SUCCESS with summary metadata
          summary_metadata = msg.metadata
          break # Done processing results
        when Messaging::Failure
          connection.reset!
          # PULL failed - transaction is now failed
          @state = :failed
          code = msg.metadata['code']
          message = msg.metadata['message']
          raise QueryError, "Query execution failed: #{code} - #{message}"
        else
          raise ProtocolError, "Unexpected message type: #{msg.class}"
        end
      end

      # Create and return Result object
      Result.new(fields, records, summary_metadata, qid)
    when Messaging::Failure
      # RUN failed - transaction is now failed
      @state = :failed
      code = response.metadata['code']
      message = response.metadata['message']
      raise QueryError, "Query execution failed: #{code} - #{message}"
    else
      raise ProtocolError, "Unexpected response to RUN: #{response.class}"
    end
  end
rescue ConnectionError
  @state = :failed
  raise
end